Module 1 Flashcards
What are the four groups of microorganisms?
Protozoa, fungi, bacteria and viruses.
What kind of nucleus does protozoa have?
True nucleus, enclosed by plasma membrane.
Give an example of protozoa.
Giardia- beaver fever
What are the subcategories of fungi?
Yeasts and molds.
How do yeasts reproduce?
Budding
Viruses rely on what to replicate?
A host
What are microorganisms measured in?
Micrometers
What are the different bacteria shapes?
Cocci, bacilli, spirilla
How many groups of bacteria are there?
Six: \+ cocci - cocci \+ bacilli - bacilli \+ spirilla - spirilla
What does the Gram reaction determine?
The effectiveness of certain antibiotics and certain disinfectants.
When does sporulation take place?
When certain nutrients are depleted.
What is contained within an endospore?
A copy of the genetic material and a tiny amount of cytoplasm.
What are examples of bacteria that form endospores?
Gangrene and tetanus
What are the characteristics of endospores?
Heat resistance
Disinfection resistance
Resistance to cold
Resistance to UV, acids, detergents, alkalis
How do bacteria reproduce?
Binary fission
Generation time is related to what?
The rate at which bacteria cause disease.
What are the phases of the growth curve and how do they relate to infection?
Lag- incubation period
Log- acute stage
Stationary- no better or worse
Death- symptoms subside
What is the convalescent period?
The time needed for complete recovery.
Which viruses are more susceptible to disinfectants?
Lipid viruses
How do viruses reproduce?
They attach to receptor sites and are taken in by endocytosis. The host cell digests the protein coat and the nucleus acid is released and directs the synthesis of vital components by the hosts machinery.
Why does viral infection normally kill the host cell?
Lysis when filled with viral particles
Diversion of the cells metabolic pathways
Destruction of the infected cell by lymphocytes
When are tumour cells formed?
When oncogenic viruses alter the nucleus acid of the host cell.
Why is it hard to treat viruses?
Because it is likely to destroy the host cells as well.
What is a microorganism?
An organism too small to be seen with the naked eye.
